Apparatus for the continuous casting of pig metal.



Patented Dec. 24, I90l.

' J. M. HARTMAN APPARATUS FOR THE CONTINUOUS CASTING 0F PIG METAL.

(Application filed Dec. 1, 1900.)

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UNITED STATES PATENT OFFICE.

JOHN M. HARTMAN, OF PHILADELPHIA, PENNSYLVANIA.

APPARATUS FOR THE CONTINUOUS CASTING OF PIG METAL.

SPECIFICATION forming part of Letters Patent No. 689,584, dated December24, 1901.

Application filed December 1, 1900. Serial No. 38,316. (No model.)

To aZZ whom it may concern:

Be it known that I, JOHN M.HARTMAN,a citizen of the United States,residing on Gowen avenue, Mount Airy, in the city and county ofPhiladelphia, State of Pennsylvania, have invented certain new anduseful Apparatus for the Continuous Casting of Pig Metal, whereofthefollowing is a specification, reference being had to the accompanyingdrawings.

My invention has relationto certain improvements in machinery for thecontinuous casting of pig metal in which a series of thin metal-molds iscarried-in continuous successionbeneath the point where the metal ispoured and thereafter through a water-trough in which the water standsat different levels, so that first the bottom of the mold and thereafterthe entire mold and pig are cooled by the water, after which the moldsare successively inverted to discharge their contents, righted, andagain carried beneath the point where the metal is poured. A convenientmechanism for carrying these molds in the form of a circular tablesurrounded by apartial annular water-trough has been described andpatented to me in Letters Patent No. 629,903, dated August 1, 1899. Iwill there'- fore not again describe the mechanism and parts which havealready been shown and described in the specification of thispriorpatcut, but will confine my description to the particular portionsto which my present improvements relate.

In the accompanying drawings, Figure 1.is a top view of a metal-moldconstructed according to my present invention. Fig. 2 is'a longitudinalcentral section through one of these molds and a portion of themoldimmediately in front of it. Fig. 3 is a view of the rear end of oneof the molds. Fig. 4 is an elevation of the frame which carries the moldwith its shaft and related parts and also showingthe relation of theseparts to the nozzle through which the metal is poured. Fig. 5 is a sideelevation showing two of the moldframes in their relation to the nozzle7 where the metal is poured and into the watertrough. Fig. 7 is anenlarged View of the mold-frame and its hanger and shaft, showing themold and the water-trough in situ. Fig. 8 is a side view, similarlyenlarged, of one of the mold-frames with its mold and hanger. Figs. 9,10, and 11 are detail views of the counterweight for balancing themoldframe and its related parts.

I will first describe the molds as constructed according to my presentinvention.

Referring to Figs. 1, 2, and 3, the body a of the mold is formed of asingle plate of wroughtiron or steel struck up into the shape thereindicated. Roughly speaking, it forms a rectangular dish sloping fromthe bottom up gradually to the long sides, which are furnished with awide flange, but having the short ends turned up more sharply andterminating in an upright edge a a. The reason for the difference in theinclination of the sides and the ends is this: The pig is less likely tostick to the mold and resist dumping the more the edges slope; but, onthe other hand, if the gradual slope of the sides is continued allaround the ends the resulting pig has formed all around it a sharp edge,which makes it exceedingly difficult for the workmen to handle itwithout cutting their hands.

-I have found that owing to the greater contraction along the line ofthe greatest length of the pig as it cools the danger of the pigstickingat either of its ends to the molds is much less than at thesides, and I have found that at least to the extent indicated in thedrawings it is practicable to make the short ends upright without dangerof the pigs sticking, and in this wayI am able to produce pigs with endsblunt enough for the workmen to handle them.

The mold is provided at its front end with an overhanging lip or bridgereaching over the rear end of the mold immediately in front of it. Thisbridge a is riveted to the top of the flange of the front end of themold. It consists of a central part b, which is formed with'asharply-divided ridge which sheds the metal falling upon it in one orthe other direction, either into the mold to which it is attached or theone in front, which it overhangs. The sides of the bridge are formedwith upright edgesor flanges 12 Z1 which, as will be seen from Fig. 1,converge in both directions from the ridge of the bridge,by whichconstruction all of the metal poured upon the bridge is accuratelyguided into one or the other of the two adjacent molds.

The rear end of the mold has no flange formed upon it and has the upperpart of its upright edge cut away, as seen at 1), thereby forming anoverflow,which prevents the mold from being overfilled and securesuniformity in the size of the pig. The molds are mounted in mold-framesin a manner similar to that shown in my previous patent, to whichreference has been made. These mold-frames are preferably attached byhangers to their rock-shafts mounted radially on a revolving table, asshown in the specification and drawings of that patent. There is alsoprovided coincidently with all but a part of the periphery of thisrevolving table a partial annular water-trough, as therein shown anddescribed. I have consequently omitted to show and describe these parts,and it will be understood that the parts which I am now about todescribe may be assembled as there shown, and I will confine my presentdescription to the parts wherein my present invention differs from thatwhich I have previously patented.

In my present invention the mold-frames t, the shape of which is bestseen in Figs. 7 and 8, diifer from those of my previous invention in theabsence of any longitudinal portion, consisting simply of twosuspensionribs, within which the mold rests and to which it may befastened, if desired, by riveting to the flange. As the molds areadvanced successively under the point of pouring, which is indicated bythe nozzle A in Fig. 5, they are filled up to the overflow b.

I have found that if the mold is filled too full any jarring of themachine may cause some escape of the metal at b after the mold hasentered the water-trough. This is a serious danger, and to prevent it Iprovide a small roller 0', fixed in position shortly in advance of thenozzle A. The shafts by which the mold-frames are carried have affixedto them a cam-incline 0, having its cam-surface formed as indicated inFig. 5. As the moldframes advance this surface comes in contact withroller 0 shortly after the mold has passed under the point where themetal is poured, and thereby a slight tip or tilt is given momentarilyto the mold sufficient to dislodge and discharge over the edge b anysurplus metal which a slight jar might otherwise thereafter cause tooverflow into the water-trough with possibility of explosion.

Notwithstanding all the precautions which have just been described someof the molten metal will occasionally slop over the edge of the mold andis liable to harden on the outside of it or against the frames whichcarry the mold. This occasions difficulty, especially where the moldsenter the water-trough. In order to prevent excessive escape of water atthis point, it is necessary that the end of some part.

the trough T, Fig. 6, should possessa configuration fitting withconsiderable closeness around the mold-frames as theyadvance. Therelation of the two is seen in Fig. 7, where the trough is shown incross-section. Under these circumstances a bit of metal splashed againstthe bottom of one of these frames and adhering thereto is liable to jamagainst this part of the trough and cause the breakage of I overcomethis difficulty by making the end of the trough free from rigid support.The distance of this end from the nearest rigid support (see Fig. 6) issufficient to allow of considerable flexibility and beneath the endwhere the molds enter the trough is upheld by the pivoted lever-arm d,which carries acounterweight 0, thereby enabling the trough to yield atthis point in the contingency which I have mentioned and avoid a break.The yielding is further facilitated by making the entrance of the troughflare, as seen at d.

In order to chill the molds instantly after they have been poured, andthus prevent the buckling due to the intense heat, I place a spray ofwater B, as shown in Fig. 5, in such relation to the nozzle A, throughwhich the metal is poured, that as the molds pass successively beneaththe pouring-spout their bottoms immediately encounter a spray of waterforced up against their under sides. This accomplishes considerablepreliminary cooling prior to the entry of the mold into the water-troughand is a better arrangement than to have the trough itself too near thepoint where the metal is poured, for although the water at the entranceof the trough is maintained at a level an inch or more below the top ofthe mold, yet extreme care must be taken to allow no water to splash ontop of the pig until all the occluded gas in the melted metal hasescaped; otherwise the skin formed over the metal of the mold by contactwith water prevents such escape, causing blowholes or cavities in thepig. Water on top of the molds at this stage also tends to cause seriousexplosions. Both of these difliculties are obviated by the use of thepreliminary spray, which quickly chills the metal next to the edge ofthe mold, forming a skin on the under side only which does not retainany occluded gas and prevents any fusion of the metal to the mold.

Each mold-frame is united to its rock-shaft R by a bracket or hanger E,formed in the shape of an inverted U. This makes it possible for themold-frame to overhang the edge of the trough and at the same timesupport the mold with reference to the rock-shaft so that when full itscenter of gravity is not greatly below the axis of the rock-shaft, thusrendering the subsequent inversion of the mold-frame for the purpose ofdumping the pig much easier. At the same time the distance between thecenter of gravity of the filled mold and the axis of the rock-shaftbeing slight, it is necessary to steady the frame While the molds arepassing through the water in order to prevent accidental rocking, withpossible overflow of metal. This is accomplished by mounting thecounterweight F on the rock-shaft upon the other side of the dependingjournal X, by which the rock-shaft is hung from its supporting-table.The lower end of the arm carrying. this counterweight has a lugf, (seeFigs. 9 and 10,) and the journal X has two projecting steps 8 s, (bestseen in Fig. 11,) so placed as to come into contact with the lug f andlimit the motion of the counterweight in that direction. In Fig. 9 thebroken lines indicate the position of the counterweight when the moldhas been inverted after dumping, while the solid lines indicate itsposition while the mold is level.

Having thus described my invention, I claim 1. In an apparatus forcasting pig metal, the combination of means for feeding molten metal ata fixed point; a series of thin metal molds; a traversing device bywhich the molds are carried in continuous succession beneath the pointwhere the molten metal is fed; and a spraying device placed beneath themolds immediately in advance of the point where the metal is fed,whereby the under side of the mold is cooled as soon as it has beenfilled, substantially as described.

2. In an apparatus for casting pig metal, a series of elongatedsubstantially rectangular metal-molds, each of which molds has a portionof its edge cut away at one of the short ends to form an overflow; atraversing device whereby the said molds are carried in continuoussuccession along the line of their greatest length beneath the pointwhere molten metal may be fed to them; and a tilting device wherebyimmediately after being filled the out-away end of each mold ismomentarily given a slight depression and any excess dischargedtherefrom, substantially as described.

3. In an apparatus for casting pigmetal; a series of elongated thinmetal-molds, each of which has atfixed to one end a bridge-piece whichoverlaps the adjacent edge of the next mold, said bridge-piece beingtransversely ridged and furnished with flanges at both sides whichconverge from the ridges; means for feeding molten metal at a givenpoint; and a traversing device by which said molds are carriedlongitudinally in continuous series beneath that point, substantially asdescribed.

4. In an apparatus for casting pig metal, a series of thin metal-molds;a water-trough; a traversing device bywhich said molds are carried incontinuous succession beneath the point where molten metal may be fedand then through the water-trough; and a tilting device wherebyimmediately after being filled and before entering the water-trough themold is momentarily given a slight inclination and any excess dischargedtherefrom, substan tially as described.-

5. In an apparatus for casting pig metal, a series of thin metal-molds;a traversing device by which said molds are carried in continuoussuccession beneath the point where molten metal may be fed; and awater-trough through which the said molds are carried by said traversingdevice after being filled, the said water-trough being provided with ayield ing support at the point where the molds first enter it,substantially as described.

6. In an apparatus for casting pig metal, a series of thin metal-molds;a series of moldframes which carry the molds; a watertrough; atraversing device with rock-shafts on which said mold-frames aremounted; and a bracket connection in the form of an inverted U, wherebythe said mold-frames are united to the rock-shaft at a height to main=tain the center of gravity of the mold and its contents not far belowthe axis of the rockshaft, while the mold depends within the wa=ter-trough, substantially as described.

7. In an apparatus for casting pig metal, a series of thin metal-molds;a series of moldframes which carry the molds; a watertrough; atraversing device with rock-shafts on which saidmold=frames are mounted;and a bracket connection in the .form of an inverted U, whereby the saidmold-frames are united to the rock-shaft at a height to maintain thecenter of gravity of the mold and its contents not far below the axis ofthe rockshaft while the mold depends within the water-trough, incombination with a counterweight on said rock-shaft and stops wherebythe motion of the counterweight is limited, substantially as described.

JOHN M. HARTMAN.

Witnesses:

JAMES H. BELL, E.- REESE.

